Well, in my opinion, this sounds cool for the most part, FURTHERMORE:
I don't care what we name this extra difficulty, but "Challenging" doesn't seem epic enough. It should be something funny, like "Epic/Oshit/Wtf."
The charts should be 4-key, unless 6-key is implemented and an "Ofuc" difficulty can be unlocked through the goals of the solo charts.
I think specific goals should be implemented; some could be AAA all difficulties, some could be AAA Easy, FC Medium, and 95% Hard, etc.
Not recording the scores for these "Ofuc" charts is wise; my vote goes for them being an extra, and I think big SP rewards should be involved.
We need 6-key. It's not too much work, and if it is, it's worth it. I think one Solo chart for each song is a good idea, and if the programming won't allow it, we should make another place for it (e.g. http://www.thirdstyle.com/play/6key). Just read Noc's concerns about this, let's make them all on the harder side? or not, I don't see the major problem, and since not a lot of people will be stepping them, we won't need many judges. Shit, Mike can judge them all.